org.apache.activemq.usage
Class Usage<T extends Usage>

java.lang.Object
  org.apache.activemq.usage.Usage<T>

All Implemented Interfaces:

Service

Direct Known Subclasses:

MemoryUsage

public abstract class Usage<T extends Usage>
extends Object
implements Service

Used to keep track of how much of something is being used so that a productive working set usage can be controlled. Main use case is manage memory usage.

Field Summary

protected String	name
protected T	parent
protected int	percentUsage
protected ReentrantReadWriteLock	usageLock
protected Condition	waitForSpaceCondition

Constructor Summary

Usage(T parent, String name, float portion)

Method Summary

protected void	addChild(T child)
void	addUsageListener(UsageListener listener)
protected int	caclPercentUsage()
ThreadPoolExecutor	getExecutor()
long	getLimit()
UsageCapacity	getLimiter()
String	getName()
T	getParent()
int	getPercentUsage()
int	getPercentUsageMinDelta()
int	getPollingTime()
long	getUsage()
float	getUsagePortion()
boolean	isFull()
boolean	isFull(int highWaterMark)
boolean	isStarted()
boolean	notifyCallbackWhenNotFull(Runnable callback)
protected void	onLimitChange()
protected void	removeChild(T child)
void	removeUsageListener(UsageListener listener)
protected abstract long	retrieveUsage()
void	setExecutor(ThreadPoolExecutor executor)
void	setLimit(long limit) Sets the memory limit in bytes.
void	setLimiter(UsageCapacity limiter)
void	setName(String name)
void	setParent(T parent)
protected void	setPercentUsage(int value)
void	setPercentUsageMinDelta(int percentUsageMinDelta) Sets the minimum number of percentage points the usage has to change before a UsageListener event is fired by the manager.
void	setPollingTime(int pollingTime)
void	setUsagePortion(float usagePortion)
void	start()
void	stop()
String	toString()
void	waitForSpace()
boolean	waitForSpace(long timeout)
boolean	waitForSpace(long timeout, int highWaterMark)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

usageLock

protected final ReentrantReadWriteLock usageLock

waitForSpaceCondition

protected final Condition waitForSpaceCondition

percentUsage

protected int percentUsage

parent

protected T extends Usage parent

name

protected String name

Constructor Detail

Usage

public Usage(T parent,
             String name,
             float portion)

Method Detail

retrieveUsage

protected abstract long retrieveUsage()

waitForSpace

public void waitForSpace()
                  throws InterruptedException

Throws:

InterruptedException

waitForSpace

public boolean waitForSpace(long timeout)
                     throws InterruptedException

Throws:

InterruptedException

waitForSpace

public boolean waitForSpace(long timeout,
                            int highWaterMark)
                     throws InterruptedException

Parameters:

timeout -

Returns:

true if space

Throws:

InterruptedException

isFull

public boolean isFull()

isFull

public boolean isFull(int highWaterMark)

addUsageListener

public void addUsageListener(UsageListener listener)

removeUsageListener

public void removeUsageListener(UsageListener listener)

getLimit

public long getLimit()

setLimit

public void setLimit(long limit)

Sets the memory limit in bytes. Setting the limit in bytes will set the usagePortion to 0 since the UsageManager is not going to be portion based off the parent. When set using Xbean, values of the form "20 Mb", "1024kb", and "1g" can be used

onLimitChange

protected void onLimitChange()

getUsagePortion

public float getUsagePortion()

setUsagePortion

public void setUsagePortion(float usagePortion)

getPercentUsage

public int getPercentUsage()

getPercentUsageMinDelta

public int getPercentUsageMinDelta()

setPercentUsageMinDelta

public void setPercentUsageMinDelta(int percentUsageMinDelta)

Sets the minimum number of percentage points the usage has to change before a UsageListener event is fired by the manager.

Parameters:

percentUsageMinDelta -

getUsage

public long getUsage()

setPercentUsage

protected void setPercentUsage(int value)

caclPercentUsage

protected int caclPercentUsage()

getName

public String getName()

toString

public String toString()

Overrides:

toString in class Object

start

public void start()

Specified by:

start in interface Service

stop

public void stop()

Specified by:

stop in interface Service

addChild

protected void addChild(T child)

removeChild

protected void removeChild(T child)

notifyCallbackWhenNotFull

public boolean notifyCallbackWhenNotFull(Runnable callback)

Parameters:

callback -

Returns:

true if the UsageManager was full. The callback will only be called if this method returns true.

getLimiter

public UsageCapacity getLimiter()

Returns:

the limiter

setLimiter

public void setLimiter(UsageCapacity limiter)

Parameters:

limiter - the limiter to set

getPollingTime

public int getPollingTime()

Returns:

the pollingTime

setPollingTime

public void setPollingTime(int pollingTime)

Parameters:

pollingTime - the pollingTime to set

setName

public void setName(String name)

getParent

public T getParent()

setParent

public void setParent(T parent)

setExecutor

public void setExecutor(ThreadPoolExecutor executor)

getExecutor

public ThreadPoolExecutor getExecutor()

isStarted

public boolean isStarted()